The inventive concept relates generally to liquid crystal display (LCD) technology. More particularly, the inventive concept relates to methods and apparatuses for driving an LCD device to improve image quality.
An LCD device comprises a liquid crystal panel having a liquid crystal layer disposed between two substrates, a backlight unit that provides light to the liquid crystal panel, and a driving circuit that drives the liquid crystal panel to display a sequence of image signals. The performance of the LCD device is limited by the response time of the liquid crystal layer, as the response time affects the rate at which images appear on the liquid crystal panel.
Researchers have developed methods to improve response time of the liquid crystal layer by comparing an image signal of a previous frame with an image signal of a current frame and then generating a compensated image signal for the current frame. In these methods, a frame memory stores the image signal of the previous frame, and the stored image signal is compressed in order to reduce the required capacity of the frame memory.
Unfortunately, these methods suffer from a variety of shortcomings that can deteriorate the quality of displayed images. For example, where noise is present in an image signal of a still image, it may be recognized as an image signal of a moving picture, and the image signal may be unnecessarily compensated such that the noise is amplified. The noise may also be amplified while the image signal is compressed and then restored, which can further deteriorate the image quality of a LCD device. In addition, in a moving picture signal, an error may occur when compressing and restoring an image signal, such that a pixel-shaking problem arises due to the error.